Mining is one of the most important global industrial activities, occurring in almost every
part of the world [1]. Mining operations and their waste disposal methods are considered one
of the main sources of environmental degradation [2]. Mining in developing countries
remains controversial due to its impact on the cultural climate, the physical environment and
the socio0economic status of the local people [3]. In Papua New Guinea (PNG), mining is an
important sector that supports the economy of the country and it is also considered the cause
for a wide range of environmental degradation, including pollution of the marine ecosystems
[4].
Discharging of mine waste tailings into aquatic systems is a common practice. They are
either discharged into a freshwater system or into the sea. Both have negative impacts on the
environment and the health of organisms including human beings. Sea Tailing Placement
(STP) is considered to be a very hazardous practice, compromising the environmental health
and safety of people so a more improved technique, the Deep Sea Tailing Placement (DSTP)
is used instead. It involves the piping of tailing effluents well below the sea level and allowed
to settle down onto the seafloor where it is considered to remain out of reach for physio0
chemical conditions that would react to render it toxic [4].
Ramu Nickel0Cobalt project is a world class mining project operated by the Chinese
Metallurgical Company (MCC Ltd) that involves the mining and refining of lateritic ores,
producing high grade nickel and cobalt intermediate products. It is the only Ni0Co mine in
PNG. Laterite ores are mined at the Krumbukari mine site and treated to remove coarse
oversized host rocks and chromites minerals, creating a slurry that is pumped to the refinery
at Basamuk in Astrolabe Bay via a 135km slurry pipeline. At the refinery, the slurry is treated
by High Pressure Acid Leaching process to solubilize Nickel and Cobalt and then
precipitated as intermediate hydroxides [5]. At the Basamuk refinery, tailings are mixed with
seawater for dilution in the mixing tank before being piped to discharge point at a depth of
150m below sea level [6]. The wastes get settled between oceanic canyons that are found at
the oceanic floor. DSTP is not new to PNG, it was used in Misima and Lihir mines [4] before
being set up in Basamuk.
Mining of Ni0Co minerals is new in the country and the disposal of tailing by DSTP is also
unpopular. Therefore, this study was aimed at assessing metal concentrations, acidity or pH
and flow velocity rate of the tailing before discharge in order to determine the ecological
safety of the tailings.
What are the main points from the above information
1. Mining is a crucial global industrial activity, but it can lead to environmental degradation and impact local communities.
2. Mining operations in Papua New Guinea, particularly the Ramu Nickel-Cobalt project, have raised concerns about environmental impact, including pollution of marine ecosystems.
3. Sea Tailing Placement (STP) is a common practice for disposing of mine waste, but it is considered hazardous. Deep Sea Tailing Placement (DSTP) is seen as an improvement in reducing environmental health risks.
4. The Ramu Nickel-Cobalt project involves mining and refining lateritic ores to produce nickel and cobalt intermediate products. Tailing disposal involves mixing with seawater for dilution before being discharged at a depth of 150m below sea level.
5. The study aims to assess metal concentrations, acidity, and flow velocity rate of the tailings before discharge to determine ecological safety.